1. Field of the Invention
The present invention relates to a filter system designed to accommodate a filter element having no center supporting tube. This allows a filter element to be constructed solely of combustible material, thus allowing the filter element to be completely incinerable.
2. Description of the Related Art
In industrial filtering applications, often the material which is to be filtered contains contaminants which must be removed and disposed of as hazardous waste. One of the acceptable ways of disposing of many types of hazardous waste is incineration performed by a licensed hazardous waste disposal facility.
One problem which previous filter systems present is that the filter element onto which the contaminates adhere have generally contained a metal or other rigid, non-combustible center support member. In order to incinerate these filter elements, the support member must either be manually removed from the filter element prior to the incineration and then separately disposed of as hazardous waste or, alternately, the entire filter element must be shredded prior to incineration.
Removal of the center support member prior to incineration presents safety problems to the workers performing the removal, adds to the cost of disposal, and increases the risk of liability to the company generating the waste. This increase in risk of liability is due to the fact that the removed support members are considered hazardous waste which must be disposed of in a licensed hazardous waste landfill. As a contributor to a hazardous waste landfill which may sometime be declared a Superfund site, the generating company, the disposal company and any transporting company which was employed to deliver the support members to the landfill, may all face future liability for the disposal. Thus, both the generating company and the disposal company would prefer to avoid this option since under current hazardous disposable waste laws, they remain liable for their hazardous waste from "cradle-to-grave".
On the other hand, in order for the entire filter element to be incinerated, a disposal facility must first be located which has the capability of shredding materials prior to incineration. Second, since the non-combustible elements of the filter element will pass through the hazardous waste incinerator and will exit as solid waste which is normally disposed of as hazardous waste in a hazardous waste landfill, the generating company retains the potential Superfund liability with this option also. This is true despite the fact that the material is not hazardous waste, since all contributors to a landfill which later becomes a Superfund site are liable for ensuing cleanup costs regardless of the types of materials they contributed. For these reasons, shredding and incinerating the entire filter elements is also an unattractive option.
The only other viable option available for disposal of most filter elements is to bury the entire filter element in a hazardous waste landfill. This option is costly and increases the risk of Superfund liability since the containers in which the filter elements are sealed for burial will eventually be breached by the soil's natural chemical processes, thus, releasing the contaminants into the soil.
Thus, to avoid potential liability, it is desirable to have completely incinerable filters. The present invention addresses this problem by providing a filter system having a permanent center tube assembly onto which fully incinerable filter elements may be replaceably attached.